Reading the log

Harmless Server Warning: ClassNotFoundException: net/minecraft/class_5616 (registrate-fabric)

What the log looks like

java\.lang\.ClassNotFoundException: net/minecraft/class_5616\)
@Mixin target net\.minecraft\.class_5616 was not found registrate-fabric\.mixins\.json:accessor\.BlockEntityRenderersAccessor

How to fix it

  1. Ignore [main/WARN] lines referencing net/minecraft/class_5616 (from registrate-fabric) as well as class_906 and class_481 (from porting_lib) — do not remove Create because of these messages.
  2. Scroll to the bottom of logs/latest.log or open the newest file in crash-reports/ and look for [main/ERROR], Encountered an unexpected exception, or Caused by: to find the real failure.
  3. If the real crash stack trace shows a NoClassDefFoundError for another client class (such as net/minecraft/class_437), check the mod package named on the 'at' line right below it (for example, client-only keybind or UI mods) and delete that mod's .jar from the server mods folder.
  4. If the server log reaches 'Done' without any [ERROR] entries but players cannot join, check the exact disconnect error shown when connecting to verify that client and server mod versions match.
LoadersFabric, Quilt, Server
SeverityWorth checking
CategoryReading the log

Check your own log

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